CN111091858B

CN111091858B - Operation method of resistive random access memory array

Info

Publication number: CN111091858B
Application number: CN201911409107.0A
Authority: CN
Inventors: 潘立阳; 孙婧瑶; 吴华强
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2021-11-09
Anticipated expiration: 2039-12-31
Also published as: WO2021136395A1; CN111091858A

Abstract

An operation method of a resistive random access memory array comprises a plurality of memory cells, a plurality of bit lines, a plurality of word lines, a plurality of block selection circuits and a plurality of initialization circuits. Each memory cell includes a resistive switching device and a switching device. The plurality of memory cells are arranged in a plurality of memory cell rows and a plurality of memory cell columns along a first direction and a second direction, and the plurality of bit lines are connected with the plurality of memory cell columns in a one-to-one correspondence mode. The operation method comprises the following steps: the plurality of block selection circuits are turned off, and the first initialization operation and the second initialization operation are performed on the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines. The resistance value of the resistance change device obtained by the operation method has better accuracy and consistency.

Description

Operation method of resistive random access memory array

Technical Field

Embodiments of the present disclosure relate to an operation method of a resistance change memory array.

Background

A Resistive Random Access Memory (RRAM) is a Memory which realizes the high-low conversion of a Resistance value by using the characteristic that the conductivity of a thin film resistive medium material is changed under the action of an external electric field. The resistive random access memory has the advantages of simple structure, high working speed, low power consumption, stable information retention, non-volatility and the like, and has huge development and application prospects.

Disclosure of Invention

At least one embodiment of the present disclosure provides a resistive random access memory array, which includes a plurality of memory cells, a plurality of bit lines, a plurality of word lines, a plurality of block selection circuits, and a plurality of initialization circuits. The array structure comprises a plurality of memory units, wherein the memory units are arranged into a plurality of memory unit rows and a plurality of memory unit columns along a first direction and a second direction, each memory unit comprises a resistance change device and a switch device, each resistance change device comprises a first electrode and a second electrode, and the first electrode of each resistance change device is electrically connected with the switch device. The plurality of bit lines extend along the second direction and are connected with the plurality of memory cell rows in a one-to-one correspondence manner, wherein each of the plurality of bit lines is electrically connected with the second electrode of the resistive switching device of the corresponding memory cell row. The word lines extend along the first direction and are connected with the memory cell rows in a one-to-one correspondence manner, wherein each of the word lines is electrically connected with the switching devices of the memory cells of the corresponding memory cell row. The plurality of block selection circuits are respectively electrically connected with the plurality of bit lines in a one-to-one correspondence manner; the plurality of initialization circuits are respectively electrically connected with the plurality of bit lines in a one-to-one correspondence manner. Each block selection circuit comprises a control end, a first end and a second end, the control end of the block selection circuit is configured to receive a block selection voltage, the first end of the block selection circuit is configured to receive a read-write operation voltage, the second end of the block selection circuit is electrically connected with a bit line correspondingly connected with the block selection circuit, and the block selection circuit is configured to respond to the block selection voltage and write the read-write operation voltage into the correspondingly connected bit line; each initialization circuit comprises a control terminal, a first terminal and a second terminal, the control terminal of the initialization circuit is configured to receive an initialization control voltage, the first terminal of the initialization circuit is configured to receive an initialization operation voltage, the second terminal of the initialization circuit is electrically connected with a bit line correspondingly connected with the initialization circuit, and the initialization circuit is configured to respond to the initialization control voltage and write the initialization operation voltage into the corresponding bit line.

In some examples, each of the plurality of initialization circuits includes a switching transistor having a gate, a first pole, and a second pole that are a control terminal, a first terminal, and a second terminal, respectively, of the initialization circuit; the switch transistor is a P-type transistor.

In some examples, the switching device includes a control terminal, a first terminal, and a second terminal, and each word line is electrically connected to the control terminals of the switching devices of the memory cells of the corresponding one of the memory cell rows; the resistive random access memory array further comprises a plurality of source lines extending along the second direction, the plurality of source lines are electrically connected with the plurality of memory cell columns in a one-to-one correspondence manner, and each of the plurality of source lines is electrically connected with the second end of the switching device of the memory cell of the corresponding memory cell column.

In some examples, the resistive random access memory array further includes a plurality of global bit lines extending along the second direction and electrically connected to the plurality of block selection circuits in a one-to-one correspondence, each global bit line being electrically connected to a first end of a correspondingly connected block selection circuit.

In some examples, the resistive switching memory array further includes an initialization operation line extending in the first direction and electrically connected to first terminals of the plurality of initialization circuits to provide the initialization operation voltage.

At least one embodiment of the disclosure also provides a resistive random access memory circuit, which includes the resistive random access memory array.

In some examples, the resistive switching memory circuit further includes an initialization control circuit configured to be electrically connected with the plurality of initialization circuits to provide the initialization operation voltage and the initialization control voltage.

In some examples, the resistive random access memory circuit further includes a column selection circuit configured to be connected with the plurality of block selection circuits to provide the read and write operation voltages to the resistive random access memory array.

In some examples, the resistive random access memory circuit further includes a program control circuit and a read control circuit, and the read and write operation voltages include a program operation voltage and a read operation voltage. The programming control circuit is connected with the column selection circuit and is configured to provide the programming operation voltage for the resistive random access memory array through the column selection circuit; the read control circuit is connected with the column selection circuit and is configured to provide the read operation voltage to the resistive random access memory array through the column selection circuit.

At least one embodiment of the present disclosure further provides an operation method, for operating the resistive random access memory array, where the operation method includes: in an initialization operation stage, the block selection circuits are turned off, and the initialization operation voltage is applied to the memory cells of the selected at least one memory cell row through the initialization circuits and the bit lines.

At least one embodiment of the present disclosure also provides an operation method of a resistance change memory array, which includes a plurality of memory cells, a plurality of bit lines, a plurality of word lines, a plurality of block selection circuits, and a plurality of initialization circuits. The memory cell array comprises a plurality of memory cell rows and a plurality of memory cell columns which are arranged along a first direction and a second direction, each memory cell comprises a resistance change device and a switch device, and the resistance change device comprises a first electrode and a second electrodeAnd the first electrode of the resistance change device is electrically connected with the switch device. The plurality of bit lines extend along the second direction and are respectively and correspondingly connected with the plurality of columns, wherein each of the plurality of bit lines is electrically connected with the second electrode of the resistive switching device of the memory cell of the corresponding memory cell column. The plurality of word lines extend in the first direction and are respectively connected to the plurality of rows, and each of the plurality of word lines is electrically connected to the switching device of the memory cell of the corresponding one of the memory cell rows. The plurality of block selection circuits are electrically connected with the plurality of bit lines in a one-to-one correspondence manner. The plurality of initialization circuits are respectively electrically connected with the plurality of bit lines in a one-to-one correspondence manner. The operation method comprises the following steps: and turning off the plurality of block selection circuits, and performing first initialization operation and second initialization operation on the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines, wherein the first initialization operation precedes the second initialization operation. The first initialization operation includes: applying a first initialization operation voltage V to memory cells of a selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines _F1. The second initialization operation includes: applying a second initialization operation voltage V to the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines _F2。

In some examples, the first initialization operating voltage V _F1 is greater than the second initialization operating voltage V _F2。

In some examples, each initialization circuit includes a control terminal, a first terminal, and a second terminal, the second terminal of each initialization circuit being electrically connected to the bit line to which the initialization circuit is correspondingly connected; the first initialization operation further includes: applying a first initialization control voltage V to control terminals of the plurality of initialization circuits _FC1 to turn on the plurality of initialization circuits, the second initialization operation further comprising: applying a second initialization control voltage V to the plurality of initialization control circuits _FC2 to turn on the plurality of initialization circuits.

In some examples, each of the plurality of initialization circuits includes a switching transistor having a gate, a first pole, and a second pole that are a control terminal, a first terminal, and a second terminal, respectively, of the initialization circuit; the switch transistor is a P-type transistor, and the first initialization control voltage V _FC1 is less than the first initialization operating voltage V _F1, the second initialization control voltage V _FC2 is less than the second initialization operation voltage V _F2。

In some examples, a difference | V between the first initialization operation voltage and the first initialization control voltage_F1－V _FC1 is less than the difference | V between the second initialization operation voltage and the second initialization control voltage_F2－V _FC2|。

In some examples, the time of the first initialization operation is greater than the time of the second initialization operation.

In some examples, the method of operation further comprises: after the second initialization operation, performing a third initialization operation on the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines, where the third initialization operation includes: applying a third initialization operation voltage V to the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines _F3。

In some examples, the first initialization operating voltage V _F1. The second initialization operation voltage V _F2. The third initialization operation voltage V_FThe size of 3 decreases in turn.

In some examples, the first initialization operation, the second initialization operation, and the third initialization operation are sequentially reduced in operation time.

In some examples, each initialization circuit includes a control terminal, a first terminal, and a second terminal, the second terminal of each initialization circuit being electrically connected to the bit line to which the initialization circuit is correspondingly connected; the first initialization operation further includes: initializing to the pluralityThe control terminal of the circuit applies a first initialization control voltage V _FC1 to turn on the plurality of initialization circuits. The second initialization operation further includes: applying a second initialization control voltage V to the plurality of initialization control circuits _FC2 to turn on the plurality of initialization circuits; the third initialization operation further includes: applying a second initialization control voltage V to the plurality of initialization control circuits _FC2 to turn on the plurality of initialization circuits, a difference | V between the first initialization operation voltage and the first initialization control voltage_F1－V _FC1, a difference | V between the second initialization operation voltage and the second initialization control voltage_F2－V _FC2, a difference | V between the third initialization operation voltage and the third initialization control voltage_F3－V _FC3| are sequentially increased.

At least one embodiment of the present disclosure further provides a resistive random access memory array including a plurality of memory cells, a plurality of bit lines, a plurality of word lines, and a plurality of block selection circuits. The array structure comprises a plurality of memory units, wherein the memory units are arranged into a plurality of memory unit rows and a plurality of memory unit columns along a first direction and a second direction, each memory unit comprises a resistance change device and a switch device, each resistance change device comprises a first electrode and a second electrode, each switch device comprises a control end, a first end and a second end, and the first electrode of each resistance change device is electrically connected with the first end of each switch device. The plurality of bit lines extend along the second direction and are respectively connected with the plurality of memory cell rows in a one-to-one correspondence manner, and each of the plurality of bit lines is electrically connected with the second electrode of the resistive switching device of the memory cell of the corresponding memory cell row. The word lines extend along the first direction and are respectively connected with the memory cell rows in a one-to-one correspondence manner, and each of the word lines is electrically connected with the control end of the switching device of the memory cell of the corresponding memory cell row. The plurality of block selection circuits are respectively electrically connected with the plurality of bit lines in a one-to-one correspondence manner, each block selection circuit comprises a control end, a first end and a second end, the control end of the block selection circuit is configured to receive a first control signal, the first end of the block selection circuit is configured to receive a read-write operation voltage, the second end of the block selection circuit is electrically connected with the bit line correspondingly connected with the block selection circuit, and the block selection circuit is configured to respond to the first control signal and write the read-write operation voltage into the correspondingly connected bit line. The second terminals of the switching devices of the memory cells of each memory cell row are electrically connected to each other.

In some examples, the resistive random access memory array further includes a plurality of source lines extending in the first direction and connected to the plurality of memory cell rows. Second ends of the switching devices of the memory cells of each memory cell row are electrically connected to each other through a corresponding one of the source lines.

In some examples, the resistive switching memory array further includes a global source line, the plurality of source lines each being electrically connected to the global source line such that the global source line electrically connects the second ends of the switching devices of the memory cells of the plurality of memory cell rows to each other.

In some examples, the second terminals of the switching devices of the memory cells of each memory cell row are both grounded.

In some examples, the resistive random access memory array further includes a plurality of initialization circuits electrically connected to the plurality of bit lines in a one-to-one correspondence, respectively, each initialization circuit including a control terminal, a first terminal, and a second terminal, the control terminal of the initialization circuit being configured to receive an initialization control voltage, the first terminal of the initialization circuit being configured to receive an initialization operation voltage, the second terminal of the initialization circuit being electrically connected to the bit line to which the initialization circuit is correspondingly connected, the initialization circuit being configured to write the initialization operation voltage to the correspondingly connected bit line in response to the initialization control voltage.

In some examples, the resistive switching memory circuit further includes a source line control circuit configured to be electrically connected with the second terminals of the switching devices of the memory cells of the one or more memory cell rows to supply a source line voltage.

In some examples, the resistive random access memory circuit further includes a column selection circuit, a program and erase control circuit, and a read control circuit. The read-write operation voltage comprises a programming operation voltage, an erasing operation voltage and a reading operation voltage; the column selection circuit is connected with the plurality of block selection circuits and configured to be connected with the plurality of block selection circuits to provide the operating voltage to the resistive random access memory array; the programming and erasing control circuit is connected with the column selection circuit and is configured to provide the programming operation voltage and the erasing operation voltage for the resistive random access memory array through the column selection circuit; the read control circuit is connected with the column selection circuit and is configured to provide the read operation voltage to the resistive random access memory array through the column selection circuit.

At least one embodiment of the present disclosure further provides a driving method, configured to drive the resistive random access memory array, where the driving method includes: the method includes applying word line voltage to a plurality of word lines to select a row of memory cells, applying source line voltage to a second end of a switching device of the selected row of memory cells to enable the switching device to be turned on and transmitting the source line voltage to a first electrode of a resistive switching device of the selected row of memory cells, and applying operating voltage to a second electrode of the resistive switching device of at least one memory cell of the selected row of memory cells through at least one of the plurality of bit lines. The operating voltages include the read-write operating voltage and an initialization operating voltage.

In some examples, the source line voltage is a ground voltage.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1A is a schematic structural diagram of a resistive switching device;

fig. 1B is a graph of voltage-current characteristics of a resistance change device;

fig. 2A is a schematic structural diagram of a resistance change memory cell;

FIG. 2B is a schematic structural diagram of a resistive random access memory array;

fig. 2C is a schematic structural diagram of a resistance change memory circuit;

fig. 3 is a schematic structural diagram of a resistive random access memory array according to at least one embodiment of the present disclosure;

fig. 4 is a signal waveform diagram illustrating an operation method of a resistive random access memory array according to at least one embodiment of the present disclosure;

fig. 5 is a flowchart of an operation method of a resistive random access memory array according to at least one embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of a resistive random access memory circuit according to at least one embodiment of the present disclosure;

fig. 7A is a schematic structural diagram of another resistive random access memory array according to at least one embodiment of the present disclosure;

fig. 7B is a schematic structural diagram of another resistive random access memory array according to at least one embodiment of the present disclosure; and

fig. 8 is a schematic structural diagram of another resistance random access memory circuit according to at least one embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. Also, the use of the terms "a," "an," or "the" and similar referents do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

A memory device (referred to as a resistive device or an RRAM device) used in the resistive random access memory has, for example, a plate capacitor shape and includes a Metal-Insulator-Metal (MIM) structure. Fig. 1A shows a schematic structural diagram of a resistive switching device, and fig. 1B shows a current-voltage (I-V) characteristic curve of the resistive switching device.

As shown in fig. 1A, the resistive switching device 10 includes a first electrode 11, a second electrode 12, and a resistive switching medium layer 13 located between the first electrode 11 and the second electrode 12, for example, the first electrode 11 is a bottom electrode (bottom electrode) of the resistive switching device 10, and the second electrode 12 is a top electrode (top electrode) of the resistive switching device.

For example, the first electrode 11 and the second electrode 12 may include a metal material such as aluminum, silver, copper, platinum, titanium, or a composite metal material, or a semiconductor material such as polysilicon. For example, the resistive switching medium layer 13 may include one or more composite medium layers; for example, the resistive switching medium layer 13 may include a metal oxide material such as hafnium oxide, copper oxide, titanium oxide, and tantalum oxide, or other dielectric materials having resistive switching characteristics.

As shown in fig. 1B, the I-V characteristic curve of the resistive switching device 10 has a hysteresis characteristic, and the curve is divided into 4 regions: a High Resistance State (HRS), a Low Resistance State (LRS), and two transition regions. When the voltage amplitude exceeds a certain threshold, the resistance of the resistive switching device can be changed, so that the resistive switching latest device 10 can be subjected to a writing operation (including a programming operation and an erasing operation).

As shown in fig. 1B, a forward voltage (V) is applied across the resistive device 10_Set) The process of changing the resistance value from the high resistance state to the low resistance state is called a Set operation, also called a write operation or a program operation; applying a reverse voltage (V) across the resistive device 10_RST) The process of changing the resistance value from the low resistance state to the high resistance state is called a Reset operation, and is also called an erase operation. For example, the voltage amplitude for performing the program operation and the erase operation is generally between 1.2V-3V. In order to prevent the resistive switching device from being broken down due to a large current suddenly generated during operation, a limiting current (CC) is required to be set to protect the device.

After the resistive device is manufactured, the resistive device is generally in a high-resistance state, a high initialization operation voltage (for example, higher than 3V) needs to be used for initializing the resistive device, and after the initialization operation, the resistive device can complete a programming operation or an erasing operation under a reduced voltage. This initialization operation is also referred to as a Forming operation. For example, it is necessary to add an initialization operation using Soft Breakdown (Soft Breakdown) of a higher voltage. For example, the initialization operation voltage required for the initialization operation is higher than that required for the Set/Reset operation, and the operation time is also longer. The initialization operation voltage V_FBetween 2V and 6V.

The resistive switching device is typically electrically connected (e.g., in series) with a switching device to form a basic memory cell. The switching device may be a two terminal element (e.g., a diode) or a three terminal element (e.g., a transistor). Fig. 2A shows a schematic structural diagram of a memory cell, and as shown in fig. 2A, the memory cell 30 includes a resistive switching device 10 and a switching device 20. For example, the switching device 20 is a three-terminal element including a control terminal 21, a first terminal 22 and a second terminal 23, and the first terminal 22 of the switching device 20 is electrically connected to the first electrode 11 of the resistive switching device 10.

For example, the first electrode 11 is a negative electrode of the resistive switching device 10, the second electrode 12 is a positive electrode of the resistive switching device 10, and when the voltage on the first electrode 11 is smaller than the voltage on the second electrode 12, the resistive switching device is forward biased; when the voltage on the first electrode 11 is greater than the voltage on the second electrode 12, the resistive switching device is reverse biased. The following examples of the present disclosure are all described as examples, but the examples of the present disclosure are not limited thereto. Those skilled in the art will readily understand that the switching device 20 may also be connected to the second electrode (positive electrode) of the resistive switching device, and the magnitude relationship of the input signal is adjusted accordingly during operation to achieve the same function.

For example, the switching device includes a diode or a transistor, thereby constituting a memory cell structure of 1D1R or 1T 1R. For example, the switching device includes a first Transistor T1, which includes a Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET), so that the 1T1R memory cell has good compatibility with existing CMOS integrated circuits.

The gate, the first pole and the second pole of the first transistor T1 are respectively used as the control terminal, the first terminal and the second terminal of the switching device. When the switching device 20 is turned on, the memory unit 30 is selected to perform read-write operation of the RRAM device, and the like; when the switching device 20 is turned off, the memory cell 30 is not selected.

It should be noted that all the transistors used in the embodiments of the present disclosure may be field effect transistors, thin film transistors, or other switching devices with the same characteristics, and all the embodiments of the present disclosure are described by taking field effect transistors as examples. The source and drain of the transistor used herein may be symmetrical in structure, so that there may be no difference in structure between the source and drain. In the embodiments of the present disclosure, in order to distinguish two poles of a transistor other than a gate, for example, one of them may be directly described as a first pole, and the other as a second pole.

A plurality of resistive random access memory units can be integrated into a RRAM memory array in a crisscross mode, and the memory device can comprise one or more memory arrays.

Fig. 2B shows a schematic diagram of a resistive random access memory array structure, where the resistive random access memory array 40 includes an array of m columns and n rows (m, n is greater than or equal to 2) of memory cells 30, a plurality of bit lines (BL <0> -BL < m-1>), a plurality of word lines (word lines) WL (WL <0> -WL < n-1>), and a plurality of source lines (source lines) SL (SL <0> -SL < m-1 >). The second electrode 12 of the resistive switching device 10 in each memory cell 30 is connected to one bit line BL, and the control terminal 21 and the second terminal 23 of the switching device 20 are connected to one word line WL and one source line SL, respectively. By applying appropriate voltages to the bit line BL, the word line WL, and the source line SL, the desired memory cell 30 can be selected for the initialization (Forming), programming (Set), erasing (Reset), and reading (Read) operations described above.

Fig. 2C shows a schematic structural diagram of a resistance change memory circuit. As shown in fig. 2C, the resistance change memory circuit includes one or more resistance change memory arrays 40 and a peripheral circuit. The peripheral circuit comprises a word line control circuit, a column selection circuit, an initialization control circuit, a programming control circuit, an erasing control circuit, a reading control circuit and the like.

The word line control circuit is connected to the word lines WL, and applies a control voltage signal to the word lines WL in a row-by-row scanning manner, for example, to control the switching devices 20 in one row of memory cells 30 (i.e., memory cells connected to the same word line WL) in each scanning period, so that one row of memory cells 30 can be selected.

The initialization control circuit generates an initialization operation voltage pulse V_FAnd applied to one or several bit lines BL through the column selection circuit to perform an initialization operation on a selected one or several memory cells 30.

The program control circuit generates a program operation voltage pulse (V)_Set) And applied to one or several bit lines BL through the column selection circuit to perform a program operation on a selected one or several memory cells 30.

The erase control circuit generates an erase operation voltage pulse (V)_RST) And applied to one or several source lines SL through the column selection circuit to perform an erase operation on a selected one or several memory cells 30.

The read control circuit generates a read operation voltage pulse V_ReadCombined pipeThe column selection circuit is applied to one or several bit lines BL to perform a read operation on a selected one or several memory cells 30.

For example, the column selection circuit may include an address decoder and may be configured to receive an address signal. The column selection circuit may receive a column address, e.g., a bit line address, of a memory cell to be accessed and decode the received bit line address by the control of the controller.

On the one hand, since the initialization operation voltage is high (for example, higher than 6V), the peripheral circuit that supplies and transmits the initialization operation voltage and the resistance change memory array 20 that receives the initialization operation voltage need to satisfy a high withstand voltage requirement. For example, as shown in fig. 2C, since the initialization control circuit generates the initialization operating voltage and transmits the initialization operating voltage to the resistive random access memory array through the column selection circuit, the transistors in the initialization control circuit, the column selection circuit and the resistive random access memory array need to have a larger size (for example, the length and width of the channel region of the transistor are larger) to meet a higher withstand voltage requirement, which not only increases the size and manufacturing cost of the circuit, but also reduces the read/write performance of the memory.

On the other hand, due to the difference of the resistive devices, the initialization time required for the resistance value change of different resistive devices is different, and the resistance value after the initialization operation is also different, so that the reliability of the subsequent rewriting operation is deteriorated and the error rate of the stored data is increased due to the difference of the resistance values. In order to improve the reliability of the subsequent rewriting operation of the resistive random access memory, memory cells with m × n capacity in the resistive random access memory array need to be selected one by one for initialization operation, and the voltage V of the initialization operation is used for_FAnd an initialization operation time (pulse time) T_FFine control is performed so that the resistance value of each resistance change device after the initialization operation is in an appropriate range. This consumes a large amount of initialization operation time and leads to an increase in test cost.

At least one embodiment of the present disclosure provides a resistive random access memory array, including a plurality of block selection circuits and a plurality of initialization circuits, where the plurality of block selection circuits are connected to a plurality of bit lines in a one-to-one correspondence, and the plurality of initialization circuits are also electrically connected to the plurality of bit lines in a one-to-one correspondence. The block selection circuit is configured to write an operating voltage to the correspondingly connected bit line in response to a block selection voltage; the initialization circuit is configured to write an initialization operation voltage to a correspondingly connected bit line in response to an initialization control voltage.

In the resistive random access memory array provided by the above embodiment of the present disclosure, by respectively providing the block selection circuit and the initialization circuit, the initialization circuit and the transmission of the initialization operating voltage are separated from the other control circuits and the transmission of the operating voltage, so that the transmission of the initialization operating voltage may not pass through the column selection circuit. For example, during the initialization operation, by controlling the block selection circuit to be turned off, the initialization operation voltage applied from the initialization circuit to the bit line is prevented from being applied to the column selection circuit, so that the withstand voltage requirement of the column selection circuit can be reduced. Therefore, the resistive random access memory array provided by the embodiment of the disclosure is beneficial to reducing the circuit range related to the higher initialization operation voltage, and reducing the voltage withstanding requirement of the circuit, thereby being beneficial to reducing the circuit size and the manufacturing cost. In addition, by arranging the initialization circuit, the initialization operation of the whole row (one row or a plurality of rows) of memory cells can be realized simultaneously, the time of the initialization operation is obviously shortened, the efficiency of the initialization test operation is improved, and the initialization test cost is reduced.

Fig. 3 is a schematic structural diagram of a resistive random access memory array 50 according to at least one embodiment of the present disclosure. As shown in fig. 3, the resistance change memory array 50 includes a plurality of memory cells 30, a plurality of bit lines BL (BL <0> -BL < m-1>), a plurality of word lines WL (WL <0> -WL < n-1>), a plurality of block selection circuits 53, and a plurality of initialization circuits 54. The plurality of memory cells 30 are arranged in n memory cell rows and m memory cell columns (m, n are 2 or more) along the first direction D1 and the second direction D2. For example, the first direction D1 and the second direction D2 are the row direction and the column direction of the array, respectively.

The plurality of bit lines BL extend along the second direction D2 and are connected in one-to-one correspondence with the plurality of memory cell columns, and each of the plurality of bit lines BL is electrically connected to the second electrode 12 of the resistive switching device 10 in each memory cell of the corresponding one of the memory cell columns.

The word lines WL extend along the first direction D1 and are connected in one-to-one correspondence with the memory cell rows, and each of the word lines WL is electrically connected to the switching device 20 of each memory cell of a corresponding one of the memory cell rows. As shown in FIG. 3, each word line WL is electrically connected to the control terminal 21 of the corresponding connected switching device 20 to provide a word line voltage V_WL。

The block selection circuits 53 are electrically connected to the bit lines BL in a one-to-one correspondence. For example, the plurality of block selection circuits 53 are arranged in the first direction D1 and are located on the first side of the array of the plurality of memory cells.

The initialization circuits 54 are electrically connected to the bit lines BL in a one-to-one correspondence. For example, the plurality of initialization circuits 54 are arranged along the first direction D1 and are located on the second side of the array of the plurality of memory cells. The second side and the first side are opposite sides of the memory cell array in the second direction D2.

Each block selection circuit 53 comprises a control terminal 530, a first terminal 531 and a second terminal 532, the control terminal 530 of the block selection circuit 53 being configured to receive a block selection voltage V_BSThe first terminal 531 of the block selection circuit 53 is configured to receive a read/write operation voltage, the second terminal 532 of the block selection circuit 53 is electrically connected to the bit line BL corresponding to the block selection circuit 53, and the block selection circuit 53 is configured to respond to the block selection voltage V_BSAnd writing the read-write operation voltage into the correspondingly connected bit line BL. For example, the read/write operation voltage includes the program operation voltage V_SetAnd a read operation voltage V_Read。

For example, the block selection circuit 53 includes a second transistor T2, and the gate, the first pole and the second pole of the second transistor T2 are respectively used as the control terminal 530, the first terminal 531 and the second terminal 532 of the block selection circuit.

Each initialization circuit 54 comprises a control terminal 540, a first terminal 541 and a second terminal 542, the control terminal 540 of the initialization circuit 54 being configured to receive an initialization control voltage V_FCThe initialization of the power supplyFirst terminal 541 of way 54 is configured to receive an initialization operating voltage V_FA second terminal 542 of the initialization circuit 54 is electrically connected to a corresponding bit line BL of the initialization circuit 54, and the block selection circuit is configured to respond to the initialization control voltage V_FCThe initialization operation voltage V_FAnd writing the correspondingly connected bit line BL.

For example, the initialization circuit 54 includes a third transistor T3 (an example of a switching transistor of the embodiment of the present disclosure), and the gate, the first pole and the second pole of the third transistor T3 are the control terminal 540, the first terminal 541 and the second terminal 542 of the initialization circuit 54, respectively.

For example, as shown in fig. 3, the resistive memory array 50 further includes a block selection line BSL extending in the first direction D1 and connected to control terminals of the plurality of block selection circuits to provide a block selection voltage V_BS。

For example, as shown in fig. 3, the resistive random access memory array 50 further includes a plurality of global bit lines (GBL <0> -GBL < m-1>), which extend along the second direction D2 and are electrically connected to the block selection circuits 53 in a one-to-one correspondence, and each global bit line GBL is electrically connected to the first end 531 of the block selection circuit 53 connected in a corresponding manner.

At least one embodiment of the present disclosure further provides a resistive random access memory array structure, which includes a plurality of the resistive random access memory arrays 50, where the plurality of resistive random access memory arrays 50 are arranged in an array along the first direction D1 and the second direction D2 to form an upper array, and the upper array also includes a plurality of rows and a plurality of columns, for example, memory cell columns of resistive random access memory arrays located in a same column in the upper array may be aligned with each other, and memory cell rows of resistive random access memory arrays located in a same row may be aligned with each other. For example, the global bit lines GBL correspond to the same row of memory cells of the resistive random access memory arrays in the resistive random access memory array structure one to one, each global bit line GBL is connected to the first ends 531 of the block selection circuits 53 in the same row of the resistive random access memory arrays in the resistive random access memory array structure, that is, the first ends 531 of the block selection circuits 53 in the same row of the resistive random access memory arrays are all electrically connected to the same global bit line GBL.

For example, the block selection voltage V may be applied to the resistive memory array 50 to be accessed_BSTo select the resistive memory array 50. This blocking (partitioning) operation can reduce the circuit load and improve the response speed of the circuit.

For example, as shown in fig. 3, the resistive random access memory array 50 further includes a plurality of source lines (SL <0> -SL < m-1>), which extend along the second direction D2, the plurality of source lines SL are electrically connected to the plurality of memory cell columns in a one-to-one correspondence, and each of the plurality of source lines SL is electrically connected to the second end 23 of the switching device 20 of the memory cell of the corresponding one of the memory cell columns.

For example, as shown in fig. 3, the resistive memory array 50 further includes a plurality of initialization operation lines FL and a plurality of initialization control lines FCL that extend in the first direction D1. The initialization operating line FL is connected to a first terminal of an initialization circuit 54 to provide the initialization operating voltage V_FThe initialization control line FCL is connected to a control terminal of the initialization circuit 54 to supply the initialization control voltage V_FC。

For example, the first transistor T1, the second transistor T2, and the third transistor T3 are N-type transistors or P-type transistors.

For example, in the case where the third transistor T3 is a P-type transistor, since the threshold voltage of the P-type transistor is less than 0 and is turned on in the case where the difference Vgs between the gate and source voltages is less than 0, the initialization control voltage V applied to the gate_FCMay be smaller than the initialization operation voltage V applied to the first pole_FFurther reducing the voltage withstand requirement of the circuit.

The embodiment of the present disclosure also provides an operation method for operating the resistive random access memory array 50. The operation method comprises the following steps: in the initialization operation stage, the plurality of block selection circuits are turned off, and an initialization operation voltage is applied to at least one selected row of memory cells through the plurality of initialization circuits and the plurality of bit lines to initialize the at least one row of memory cells.

In the following, the first transistor T1 and the second transistor T2 are both N-type transistors, and the third transistor T3 is a P-type transistor, however, the embodiments of the present disclosure are not limited to the types of the first to third transistors, and when the types of the transistors are changed, the magnitude relationship between the signals is adjusted accordingly so that the circuits achieve the same function.

For example, referring collectively to FIG. 3, during this initialization phase of operation, a positive word line voltage V is applied via a selected word line WL (e.g., corresponding to one or more rows of memory cells connected thereto)_WLAnd controls the plurality of source lines SL to be grounded so that the switching devices 20 (the first transistors T1) in the one or more rows of memory cells 30 are turned on, i.e., the one or more rows of memory cells are selected.

For example, in the initialization operation stage, a block selection voltage V is applied to the block selection circuit 53 through the block selection line BSL_BSThe block selection circuit 53 is turned off. For example, the control block select line BSL is grounded such that the second transistor T2 is turned off. Thus, during the initialization operation in the initialization operation stage, the block selection circuit is turned off to separate the transmission of the initialization circuit and the initialization operation voltage from the transmission of other control circuits and operation voltages, thereby reducing the circuit range involved by the initialization operation voltage and reducing the withstand voltage requirement and size of the circuit.

For example, the initialization operation voltage V is applied to the initialization operation lines FL_FAn initialization control voltage V is applied to the initialization control line FCL_FCThe third transistor T3 is turned on to turn on the initialization circuit and apply the initialization operation voltage V_FAnd transferred to the second electrode 12 of the resistive switching device 10 of the selected at least one row of memory cells through the initialization circuit 54 and the plurality of bit lines BL. Meanwhile, the first electrode 11 of the resistive device is grounded via the corresponding source line SL through the turned-on switching device 20, so that a forward voltage difference V is introduced at two ends of the resistive device_FThe resistive random access device is in soft breakdown to change from an initial high-resistance state to a low-resistance state, so that at least one row of memory cells selected are subjected to initialization (Forming) operation at the same time.

For example, the third transistor T3 is a P-type transistor, and the initialization voltage V is applied to the initialization operation line FL during the initialization operation phase_FAn initialization control voltage V is applied to the initialization control line FCL_FCAnd makes the initialization operation voltage V_FIs higher than the initialization control voltage V_FCThereby turning on the third transistor T3, the initialization circuit 54 is turned on. For example, the initialization operating voltage V_FBetween 2V and 6V. For example, the initialization control voltage V_FCPulse time (T) of_F) In the range of 1 microsecond to 10 milliseconds.

Fig. 4 is a waveform diagram illustrating a process of performing an initialization operation on different memory cells simultaneously in an initialization operation stage in an operation method according to an embodiment of the disclosure.

Fig. 4 schematically shows waveforms of voltage and current during an initialization operation of the resistive switching devices in three memory cells (R1, R2, R3) located in the same row but different columns. At the beginning of the initialization operation phase, the resistance value of the resistive switching device 10 in the selected memory cell is high, the on-state current is small, the current flowing through the corresponding third transistor T3 is also small, the third transistor T3 works in the linear region, the voltage difference between the first pole and the second pole of the third transistor T3 is small, and the initialization operation voltage V is small_FCan be regarded as being applied to the resistance change device 10 in its entirety; as the initialization operation proceeds, at the resistance change time (T)_t) The resistance value of the resistance change device 10 becomes low, the on current increases, and the current flowing through the third transistor T3 also increases; when the current increases to the saturation current (I) of the third transistor T3_DS,Sat) When the third transistor T3 enters the saturation region, the voltage difference between the first and second poles of the third transistor T3 increases and the on-current remains unchanged, and the voltage transmitted to the resistive switching device 10 decreases and finally stops at the lowest critical voltage (V) of the initialization operation_Form,TH) When the external voltage is higher than the lowest critical voltage, the resistance value of the resistance change device is reduced; when the external voltage is lower than the lowest critical voltageThe resistance value of the resistance change device is kept unchanged. The lowest critical voltage is an inherent property of the resistive switching device, and is related to a material, a process, a structure and the like of the resistive switching device. After the initialization operation, the resistance value of the resistive device 10 is the ratio V of the lowest critical voltage to the saturation current_Form,TH/I_DS,Sat。

Therefore, the operation method provided by the embodiment of the present disclosure can limit the voltage and the maximum on current applied to the two ends of the resistive switching device 10 in the selected memory cell by introducing the initialization circuit, that is, limit the resistance value of the resistive switching device after the initialization operation. Therefore, although the time required for the resistance value change of a plurality of memory cells in one or more rows selected for initialization operation at the same time is different due to the difference of structures, materials, processes and the like, the resistance values finally reached by the memory cells are the same or similar, and the consistency and reliability of the memory cells are obviously improved; compared with the one-by-one operation, the initialization operation time is greatly shortened.

For example, as shown in fig. 4, the resistance change times of the memory cells R1, R2, R3 in the same row but different columns are sequentially increased (delayed), but the resistive switching device 10 finally reaches the same resistance value V_Form,TH/I_DS,SatAnd the consistency is achieved.

For example, by the above-described operation method, the saturation current I to the third transistor T3 can be passed_DS,SatSetting is performed so as to set the resistance value of the resistance change device after the initialization operation. For example, the initialization operation may have a great influence on the reliability of the subsequent Set/Reset operation, and if the resistance value of the resistance change device after the initialization operation is too high, the reliability of the subsequent Set operation may be deteriorated; on the contrary, if the resistance value of the resistance change device is too low after the initialization operation, the reliability of the subsequent Reset operation becomes poor. Therefore, the operation method can finely control the resistance value of the resistive switching device in the memory cell after the initialization operation, so that the resistance value of the resistive switching device after the initialization operation is in a proper range, thereby improving the reliability of the subsequent Set and Reset rewriting operations. For example, the resistance value is in a write operation after an initialization operation of the resistive switching deviceBetween the maximum resistance (corresponding to the high resistance state) and the minimum resistance (corresponding to the low resistance state).

Compared with the traditional technology of performing initialization operation bit by bit, the resistive random access memory array and the operation method thereof provided by the embodiment of the disclosure can realize simultaneous initialization operation of one whole line or multiple lines of memory cells under the condition of not sacrificing consistency and reliability of the memory cells, thereby remarkably shortening the time of the initialization operation, improving the efficiency of the initialization test operation and reducing the cost of the initialization test.

In addition, as the time of the initialization operation is shortened, the time of the memory array stressed by the initialization operation voltage is shortened, and the switching device of the memory unit can be designed by adopting a low-voltage MOSFET transistor with the voltage withstanding requirement below 3V, thereby greatly reducing the area and the manufacturing cost of the memory array.

For example, the operating method further includes a programming operation phase in which a forward voltage is applied to the resistive device in the selected memory cell to thereby implement a programming operation on the selected memory cell; in the erasing operation stage, a reverse voltage is applied to the resistive device in the selected memory cell to implement the erasing operation on the selected memory cell. The resistance value of the resistance change device is changed from high to low through the programming operation, and is changed from low to high through the erasing operation.

For example, the selected memory cell is the memory cell to be programmed in the programming operation phase, e.g., one or more of a row of memory cells.

For example, referring to fig. 3 in combination, a bit line voltage is applied to the second electrode (positive electrode) of the resistive device of the selected memory cell through the block selection transistor and the bit line, a source line voltage is applied to the first electrode (negative electrode) of the resistive device of the selected memory cell through the source line and the switching device, and the resistive device is forward biased or reverse biased by controlling the magnitudes of the bit line voltage and the source line voltage, so that a program operation or an erase operation is performed on the selected memory cell.

For example, in order to simplify the circuit, the lower of the bit line voltage and the source line voltage may be set to a ground voltage, that is, the corresponding signal line (bit line or source line) is controlled to be grounded; accordingly, the higher voltage (program operation voltage or erase operation voltage) is designed to be a positive voltage.

For example, in the program operation phase, the bit line voltage is the program operation voltage; in the erasing operation stage, the source line voltage is the erasing operation voltage.

The operation method provided by the embodiment of the present disclosure is exemplarily described below with reference to fig. 3.

Referring to fig. 3 in combination, during a program operation phase, a plurality of initialization circuits are turned off and a block selection circuit is turned on; applying a positive program operation voltage V to a selected memory cell through at least one block selection circuit 53 and at least one bit line BL_SetAnd controlling the source line SL corresponding to the selected memory cell to be grounded, so as to apply forward voltage to the resistive switching device to perform programming operation on the memory cell.

For example, the second transistor T2 is N-type, and the positive block selection voltage V is set_BSApplying to the block selection line of the selected resistive random access memory array to program the operating voltage V_SetIs applied to at least one global bit line GBL to turn on the corresponding at least one block selection circuit, and applies the program operation voltage V_SetTransferred to the corresponding bit line BL and applied to the second electrode 12 of the resistance change device of the selected memory cell.

For example, the word line voltage V_WLThe source line voltage is applied to the control terminal of the switching device 20 (first transistor T1) in one row of memory cells 30 through the selected word line WL (corresponding to the connection of the selected memory cell), and the source line voltage is applied to the source line SL corresponding to the selected memory cell. For example, the first transistor T1 is an N-type transistor, and the word line voltage V_WLThe source line SL is grounded for a positive voltage, so that the switching device in the selected memory cell in the row of memory cells is turned on, and the first electrode 11 of the resistive switching device is grounded.

For example, the program operation voltage V_SetIs between 1.2V-3V and the pulse time is between 1 nanosecond and 10 microseconds.

For example, the method of operation further comprises: on-going eraserExcept for the operation stage, a plurality of initialization circuits are closed, and a block selection circuit is opened; applying a positive erase operation voltage V to the selected memory cell through the source line SL_RSTAnd the bit line BL corresponding to the selected memory cell is controlled to be grounded by at least one block selection circuit 53, so that a reverse voltage is applied to the resistive switching device to perform an erase operation on the memory cell.

For example, the second transistor T2 is N-type, and the positive block selection voltage V is set_BSThe voltage is applied to a block selection line of a selected resistive random access memory array, and at least one global bit line GBL is grounded to turn on a corresponding at least one block selection circuit, and the second electrode 12 of the resistive random access device of the selected memory cell is grounded.

For example, a positive word line voltage V_WLThe erase operation voltage V is applied to the control terminal of the switching device 20 (first transistor T1) in one row of memory cells 30 through the selected word line WL (corresponding to the connection of the selected memory cell) and_RSTan erase operation voltage V applied to at least one source line SL to turn on a switching device of a selected memory cell_RSTTo the first electrode 11 of the resistance change device of the selected memory cell.

For example, the erase operation voltage V_RSTIs between 1.2V-3V and the pulse time is between 1 nanosecond and 10 microseconds.

For example, the operating method further comprises a read operation phase. For example, in the read operation phase, the plurality of initialization circuits are turned off, and at least one block selection circuit (corresponding to the selected memory cell) is turned on, thereby performing a read operation on the selected memory cell.

For example, the selected memory cell is a memory cell to be read.

Referring to fig. 3 in combination, the second transistor T2 is, for example, an N-type transistor, and the positive block selection voltage V is applied_BSApplied to a block select line BSL of a selected resistive random access memory array, and applying a read operation voltage V_ReadIs applied to at least one global bit line GBL (corresponding to the selected memory cell connected) to turn on the at least one block selection circuit and to turn on the read operation voltage V_ReadTo the second electrode 12 of the resistance change device of the selected memory cell through the corresponding bit line BL.

For example, a positive word line voltage V_WLThe switching device in the selected memory cell in a row of memory cells 30 is turned on by applying a selected word line WL (corresponding to the connection of the selected memory cell) to the control terminal of the switching device 20 (first transistor T1) and grounding the plurality of source lines SL, and the first electrode 11 of the resistive switching device is grounded.

Positive V is introduced to two ends of electrodes of resistance change device of selected memory cell_ReadA voltage difference and generates a conduction read current (I)_Read). The resistance value of the resistance change device is high, and the reading current is small; the resistance value is low and the reading current is large. The read current is detected by the peripheral read control circuit to complete the read operation of the selected memory cell.

For example, the read operation voltage V_ReadBetween 0.1V and 1.2V, pulse time (T)_Set) In the range of 1 nanosecond to 10 microseconds.

At least one embodiment of the present disclosure further provides an operation method for operating the resistive random access memory array 50. The operation method comprises the step of carrying out the initialization operation on the resistive random access memory array for multiple times in an initialization operation stage. For example, the number of initialization operation steps is between 2 and 100, or more. For example, due to differences in the structure, material, and process of each memory cell, there are differences in the performance of the resistive switching device and the switching device in each memory cell. E.g., the lowest critical voltage (V) of each resistive switching device_Form,TH) In contrast, the saturation current (I) of each switching device under the same voltage condition_DS,Sat) Therefore, the resistance value of the resistive device after the initialization operation is different, and a resistance value distribution exists.

By the multi-step initialization operation method, the initialization operation voltage (V) of each initialization operation can be adjusted in turn_F) And the initialization control voltage (V)_FC) The resistance values of the resistance change devices of the memory cells operated in the whole row (one or more rows) are sequentially reduced to finally reach the required target value. By using the methodThe resistance value of the obtained resistance change device has better accuracy and consistency.

For example, the resistance value distribution of the resistance change device becomes narrower and the average value is lower after each initialization operation. For example, the standard deviation of the resistance value distribution of the plurality of resistance change devices decreases in sequence after each initialization operation, and the weighted average value of the resistance values decreases in sequence.

For example, for this multi-step initialization operation, the initialization operation voltage V_FThe time sequence decreases sequentially with the initialization operation.

By controlling the initialisation operating voltage V_FThe saturation current increasing effect caused by the short channel effect of the third transistor T3 and other factors can be relieved, so that the standard deviation of the resistance value distribution of the resistance change device after initialization operation is reduced, and the resistance value distribution is narrower and more uniform.

For example, for the multi-step initialization operation, the difference | V between the initialization operation voltage and the initialization control voltage_F－V_FCL increases in order along with the initialization operation time sequence.

The saturation current of the third transistor T3 is I_ds,sat＝α(Vgs-Vth)²Where α is related to the material and size of the third transistor T3. Since the difference between the initialization operation voltage and the initialization control voltage (i.e., Vgs) determines the magnitude of the saturation current of the third transistor T3, this arrangement may cause the saturation current I in each initialization operation_ds,satSequentially increase and then sequentially decrease the average value (e.g., weighted average value) of the resistance values of the resistive devices of the memory cells operated in the entire row (one or more rows).

For example, for the multi-step initialization operation, the time T of the initialization operation_FThe time sequence decreases sequentially with the initialization operation.

The resistance value of the resistance change device is gradually reduced along with the progress of the initialization operation, and the initialization time required for the resistance value change is gradually reduced, so that the initialization operation time of the multi-step initialization operation is sequentially reduced along with the progress of the initialization operation, and the power consumption of the circuit can be saved. For example, the time of the first step initialization operation may be set to be longest.

For example, the method of operation includes: and turning off the plurality of block selection circuits, and performing first initialization operation and second initialization operation on at least one selected row of memory cells through the plurality of initialization circuits and the plurality of bit lines. The first initialization operation includes: applying a first initialization operation voltage V to the selected at least one row of memory cells through the plurality of initialization circuits and the plurality of bit lines _F1; the second initialization operation includes: applying a second initialization operation voltage V to the selected at least one row of memory cells through the plurality of initialization circuits and the plurality of bit lines _F2. The first initialization operation precedes the second initialization operation.

For example, the first initialization operation voltage V _F1 and the second initialization operation voltage V _F2 are different.

For example, referring collectively to fig. 3, the first and second initialization operating voltages are each configured to be applied to the second electrode 12 (positive electrode) of the resistive switching device of the memory cell such that the resistive switching device is forward biased.

For example, the first initialization operation further includes: applying a positive word line voltage V via a selected word line WL (corresponding to one or more rows of selected memory cells connected thereto)_WLAnd controls the plurality of source lines SL to be grounded so that the switching devices 20 (the first transistors T1) in the selected row or rows of memory cells 30 are turned on.

For example, the second initialization operation further includes: applying a positive word line voltage V via a selected word line WL (corresponding to one or more rows of selected memory cells connected thereto)_WLAnd controls the plurality of source lines SL to be grounded so that the switching devices 20 (the first transistors T1) in the selected row or rows of memory cells 30 are turned on.

For example, the first initialization operation further includes: applying a first initialization control voltage V to the control terminals of the plurality of initialization circuits _FC1 to turn on the plurality of initialization circuits; the second initialization operation further includes: applying a second initialization control voltage V to the plurality of initialization control circuits _FC2 to connect the plurality ofThe initialization circuit is turned on.

For example, the first initialization operation voltage V _F1 is greater than the second initialization operation voltage V _F2. By controlling the initialisation operating voltage V_FThe saturation current increasing effect caused by the short channel effect of the third transistor T3 and other factors can be relieved, so that the standard deviation of the resistance value distribution of the resistance change device after initialization operation is reduced, and the resistance value distribution is narrower and more uniform.

For example, the difference | V between the first initialization control voltage and the first initialization operation voltage_F1－V _FC1 is less than the difference V between the second initialization operation voltage and the second initialization control voltage_F2－V _FC2| (absolute).

The saturation current of the third transistor T3 is I_ds,sat＝α(Vgs-Vth)²Where α is related to the material and size of the third transistor T3. Since the difference between the initialization operation voltage and the initialization control voltage (i.e., Vgs) determines the magnitude of the saturation current of the third transistor T3, this arrangement may cause the saturation current I in each initialization operation_ds,satAnd the resistance values of the resistance change devices of the memory cells operated in the whole row (one or more rows) are sequentially increased, and the average values of the resistance change devices of the memory cells operated in the whole row are sequentially decreased.

For example, the time of the first initialization operation is longer than the time of the second initialization operation.

In other examples, the first initialization operation voltage is a difference | V between the first initialization control voltages_F1 －V _FC1| may also be the difference | V between the second initialization operation voltage and the second initialization control voltage_F2－V _FC2| (absolute value) are the same.

The third transistor T3 may be a P-type or an N-type, and the initialization circuit is turned on by selecting an appropriate initialization operation voltage and an initialization control voltage according to the type of the corresponding transistor. For example, the third transistor T3 is a P-type transistor, and the first initialization control voltage V _FC1 is less than the first initialization operation voltage V _F1 to initialize said pluralityThe circuit is started and the second initialization control voltage V _F2 is less than the second initialization operation voltage V _FC2 to turn on the plurality of initialization circuits.

When the third transistor T3 is P-type, the control voltage V is initialized_FCLess than the initial operating voltage V_FWhen a certain initialization operation voltage is selected to perform the initialization operation on the memory cell, the third transistor T3 is set to P-type, which reduces the voltage endurance requirement of the circuit.

For example, the method of operation further comprises: after the second initialization operation, a third initialization operation is performed on the selected at least one row of memory cells through the plurality of initialization circuits and the plurality of bit lines. The third initialization operation includes: applying a third initialization operation voltage V to the selected at least one row of memory cells through the plurality of initialization circuits and the plurality of bit lines _F3。

For example, the first initialization operation voltage V _F1. Second initialization operating voltage V _F2. Third initialization operating voltage V_FThe size of 3 decreases in turn.

For example, the third initialization operation further includes: applying a third initialization control voltage V to the plurality of initialization control circuits _FC3 to turn on the plurality of initialization circuits.

For example, the first initialization operation voltage V _F1. Second initialization operating voltage V _F2. Third initialization operating voltage V _F3. First initialization control voltage V _FC1. Second initialization control voltage V _FC2. Third initialization control voltage V_FCThe sizes of 3 are all between 2V and 6V.

For example, the operation times of the first initialization operation, the second initialization operation, and the third initialization operation decrease in order.

Fig. 5 is a flowchart illustrating an operation method of a resistive random access memory array according to at least one embodiment of the present disclosure. Fig. 5 shows an example of performing the initialization operation three times, however, the number of initialization operation steps is not limited by the embodiment of the present disclosure.

Referring to fig. 3 and 5 in combination, the operating method includes steps S1-S4.

Step S1: the plurality of block selection circuits are turned off.

For example, a block selection voltage V is applied to the block selection circuit 53 through the block selection line BSL_BSThe block selection circuit 53 is turned off. For example, the second transistor T2 is an N-type transistor, and connects the block select line BSL to ground, i.e., the block select voltage V_BSIs 0.

By setting the block selection circuit to be turned off to separate the transmission of the initialization circuit and the initialization operating voltage from the transmission of other control circuits and operating voltages, the circuit range related to the initialization operating voltage is reduced, and the voltage withstand requirement and the size of the circuit are reduced.

For example, the first transistor T1 is an N-type transistor, and a word line voltage V is applied through a selected word line WL (corresponding to one or more rows of selected memory cells connected thereto)_WLAnd the source lines SL are grounded, so that the switching devices 20 (the first transistors T1) in the one or more rows of memory cells 30 are turned on, i.e., the one or more rows of memory cells are selected. The first electrode 21 of the switching device 20 is grounded.

Step S2: and performing first initialization operation on at least one row of memory cells selected by the plurality of initialization circuits and the plurality of bit lines.

For example, the first initialization operation includes applying the first initialization operation voltage V to the initialization operation lines FL, respectively_F1, applying a second initialization control voltage V to the initialization control line FCL _FC2 make the initialization circuit turn on and operate the initialization voltage V _F1 to the second electrode 22 of the switching device. A positive voltage difference V exists between the two ends of the resistive device 20_F1, the resistance value of which is reduced from the initial value to the first resistance value.

For example, the third transistor T3 is a P-type transistor, and the first initialization voltage V is applied during the initialization operation_FIs greater than the first initialization control voltage V_FCThereby turning on the third transistor T3, the initialization circuit 54 is turned on. For example, the first initializationOperating voltage V _F1 is between 2V and 6V. For example, the first initialization control voltage V _FC1 pulse time (T)_F) In the range of 1 microsecond to 10 milliseconds.

For example, the plurality of resistive switching devices have a first resistance distribution and a first average resistance (e.g., a weighted average) after a first initialization operation. The standard deviation of the first resistance distribution is reduced compared to the standard deviation of the initial resistance distribution, and the first average resistance is reduced compared to the initial average resistance.

Step S3: and performing second initialization operation on at least one row of memory cells selected by the plurality of initialization circuits and the plurality of bit lines.

For example, the second initialization operation includes: respectively applying an initialization voltage V to the initialization operation lines FL _F2, an initialization control voltage V is applied to the initialization control line FCL _FC2 make the initialization circuit turn on and operate the initialization voltage V _F2 to the second electrode 22 of the switching device. A positive voltage difference V exists between the two ends of the resistive device 20_F2, the resistance value is reduced from the first resistance value to the second resistance value.

For example, the third transistor T3 is a P-type transistor, and the second initialization voltage V is set during the initialization operation _F2 is greater than the second initialization control voltage V _FC2, thereby turning on the third transistor T3, the initialization circuit 54 is turned on. For example, the second initialization operation voltage V _F2 is between 2V and 6V. For example, the second initialization control voltage V_FCThe pulse time of 2 is in the range of 1 microsecond to 10 milliseconds.

For example, the plurality of resistive switching devices have a second resistance distribution and a second average resistance (e.g., a weighted average) after the second initialization operation. The standard deviation of the second resistance distribution is smaller than that of the first resistance distribution, that is, the resistance distribution is more converged through the second initialization operation. For example, the second average resistance value is smaller than the first average resistance value.

Step S4: and performing a third initialization operation on the selected at least one row of memory cells through the plurality of initialization circuits and the plurality of bit lines.

For example, the third initialization operation includes: respectively applying an initialization voltage V to the initialization operation lines FL _F3, applying an initialization control voltage V to the initialization control line FCL _FC3 make the initialization circuit turn on and operate the initialization voltage V _F3 to the second electrode 22 of the switching device. A positive voltage difference V exists between the two ends of the resistive device 20_F3, the resistance value is reduced from the second resistance value to a third resistance value.

For example, the third transistor T3 is a P-type transistor, and the third initialization voltage V is set during the initialization operation _F3 is greater than the third initialization control voltage V _FC3, thereby turning on the third transistor T3, the initialization circuit 54 is turned on. For example, the third initialization operation voltage V _F3 is between 2V and 6V. For example, the third initialization control voltage V_FCThe pulse time of 3 is in the range of 1 microsecond to 10 milliseconds.

For example, the plurality of resistive devices have a third resistance distribution and a third average resistance (e.g., a weighted average) after the third initialization operation. The standard deviation of the third resistance distribution is smaller than that of the second resistance distribution, that is, the resistance distribution is more converged through the third initialization operation. The third average resistance value is smaller than the second average resistance value.

At least one embodiment of the present disclosure further provides a resistive random access memory circuit, which includes the resistive random access memory array 50. Fig. 6 is a schematic structural diagram of a resistive random access memory circuit 60 according to at least one embodiment of the present disclosure.

For example, the resistance change memory circuit 60 further includes an initialization control circuit 61, and the initialization control circuit 61 is configured to be electrically connected to the plurality of initialization circuits 54 to supply the initialization operation voltage V_FAnd the initialization control voltage V_FC。

For example, as shown in fig. 6, the resistive random access memory circuit 60 further includes a column selection circuit 62, and the column selection circuit 62 is configured to provide the read and write operation voltage to the resistive random access memory array 50. For example, the read/write operation voltage includes a program operation voltage V_SetErase operation voltage V_RSTAnd a read operation voltage V_Read。

For example, the program operation voltage V_SetAnd a read operation voltage V_ReadThe erasing operation voltage V is supplied to the resistive random access memory array through the bit line BL_RSTThe memory resistive switching array is supplied through a source line SL. However, the disclosed embodiments are not so limited. In other examples, for example, the program operation voltage V_SetErase operation voltage V_RSTAnd a read operation voltage V_ReadThe resistive memory resistance array can be provided with bit lines BL.

For example, the column selection circuit 62 is electrically connected to a plurality of global bit lines GBL.

For example, as shown in fig. 6, the resistance change memory circuit 60 further includes a program control circuit 63, an erase control circuit 64, and a read control circuit 65.

For example, the program control circuit 63 is connected to the column selection circuit 62, and is configured to provide the program operation voltage V to the resistive random access memory array 60 through the column selection circuit 62_Set. For example, in a program operation phase, the program control circuit 63 applies a program operation voltage V to a selected memory cell through the column selection circuit 62 and at least one bit line BL_SetAnd applying a forward voltage to the resistive switching device to perform a programming operation on the memory cell.

For example, the erase control circuit 64 is connected to the column selection circuit 62 and configured to provide the erase operation voltage V to the resistive random access memory array 60 through the column selection circuit 62_RST. For example, in the erasing operation stage, the erasing control circuit 64 applies the erasing operation voltage V to the selected memory cell through the column selection circuit 62 and at least one source line SL_RSTAnd applying a reverse voltage to the resistive switching device to perform an erasing operation on the memory cell.

For example,the read control circuit 65 is connected to the column selection circuit 62, and is configured to supply a read operation voltage V to the resistive random access memory array 60 through the column selection circuit 62_Read. For example, in a read operation phase, the read control circuit 65 applies a read operation voltage V to a selected memory cell through the column selection circuit 62 and at least one bit line BL_ReadTo apply a forward voltage to the resistive switching device for a read operation.

For example, as shown in fig. 6, the resistance change memory circuit 60 further includes a block selection control circuit 66 and a word line control circuit 67.

For example, the block selection control circuit 66 is configured to be connected with the block selection line BSL to supply the block selection voltage V to the resistive memory array 50_BS。

For example, the word line control circuit 67 is configured to provide the word line voltage V to the resistive memory array 50_WL. For example, the word line control circuit 67 is electrically connected to a plurality of word lines WL.

For more details, reference may be made to the foregoing description of the operation method embodiments, which are not repeated herein.

The embodiment of the present disclosure also provides a resistive memory array, in which the second ends of the switching devices of the memory cells of each memory cell row are electrically connected to each other.

Fig. 7A is a schematic diagram of a resistive random access memory array 70 according to at least another embodiment of the present disclosure. As shown in fig. 7A, the resistance change memory array 70 includes a plurality of memory cells 30, a plurality of bit lines BL, a plurality of word lines WL, and a plurality of block selection circuits 53.

The plurality of memory cells 30 are arranged in n memory cell rows and m memory cell columns (m, n are 2 or more) along the first direction D1 and the second direction D2, each memory cell 30 includes a resistive switching device 10 and a switching device 20; the resistive switching device 10 includes a first electrode 11 and a second electrode 12, and the switching device 20 includes a control terminal 21, a first terminal 22, and a second terminal 23; the first electrode 11 of the resistive switching device 10 is electrically connected to the first terminal 22 of the switching device 20. The second terminals 23 of the switching devices 20 in the memory cells 30 of each memory cell row along the first direction D1 are electrically connected to each other.

The bit lines BL extend in the second direction D2 and are connected to the memory cells 30 in a row, and each of the bit lines BL is electrically connected to the second electrode 12 of the resistive switching device 10 in the corresponding memory cell 30 in the row.

The plurality of word lines WL extend along the first direction D1 and are connected in a one-to-one correspondence with the plurality of rows of memory cells 30, and each of the plurality of word lines WL is electrically connected to the control terminal 21 of the switching device 20 of a memory cell in the corresponding row of memory cells 30.

The plurality of block selection circuits 53 are respectively electrically connected to the plurality of bit lines BL in a one-to-one correspondence, each block selection circuit 53 includes a control terminal 530, a first terminal 531, and a second terminal 532, the control terminal 530 of the block selection circuit 53 is configured to receive a block selection voltage V_BSThe first terminal 531 of the block selection circuit 53 is configured to receive a read/write operation voltage, the second terminal 532 of the block selection circuit 53 is electrically connected to the bit line BL corresponding to the block selection circuit 53, and the block selection circuit is configured to respond to the block selection voltage V_BSAnd writing the read-write operation voltage into the correspondingly connected bit line BL. For example, the read/write operation voltage includes a program operation voltage V_SetErase operation voltage V_RSTAnd a read operation voltage V_Read。

As shown in fig. 7A, the second terminals 23 of the switching devices 20 in each row of the memory cells 30 are directly electrically connected to each other at the same potential in the first direction D1, without providing a source line for selecting the potentials of the second terminals 23 of the switching devices in one row of the memory cells in the second direction D2. The arrangement is favorable for reducing the density of the routing in the second direction, simplifying the manufacturing process and improving the yield.

For example, as shown in fig. 7A, the resistive random access memory array may further include a plurality of source lines SL (SL <0> -SL < n/2-1>) extending in the first direction D1, i.e., in parallel with the plurality of word lines WL. The plurality of source lines SL are correspondingly connected with the plurality of memory cell rows, and the second ends of the switching devices of the memory cells of each memory cell row are electrically connected to each other through a corresponding one of the source lines SL.

For example, the source lines SL are connected to the memory cell rows in a one-to-one correspondence. The second terminals 23 of the switching devices 20 of the memory cells 30 of each memory cell row are electrically connected to a corresponding one of the source lines SL, and are electrically connected to each other through the source line SL.

For example, the source lines SL may be insulated from each other or electrically connected to each other. The disclosed embodiments are not so limited.

For example, as shown in fig. 7A, every two adjacent rows of memory cells share one source line SL. The second ends of the switching devices of every two adjacent rows of memory cells are electrically connected to the same source line SL. Therefore, the wiring density can be reduced, and the process cost is reduced.

For example, as shown in fig. 7B, the resistive random access memory array 60 further includes a Global Source Line (GSL), and the second ends of the switching devices in each memory cell row are electrically connected to the global source line GSL, that is, the global source line electrically connects the second ends of the switching devices in the resistive random access memory array 60 to each other. The global source line GSL is used to connect the second terminals of the plurality of switching devices to a peripheral circuit (e.g., a source line control circuit in fig. 8) to supply a source line voltage to the plurality of memory cells. The global source line GSL may also be directly grounded.

For example, as shown in fig. 7B, the global source line GSL extends in the second direction D2.

For example, as shown in fig. 7B, the number of the global source lines GSL is two, and the two global source lines GSL are respectively located on opposite sides of the memory cell array formed by the plurality of memory cells 30 in the first direction D1.

For example, the plurality of source lines SL are each electrically connected to two global source GSL lines at both sides.

For example, the second terminals 23 of the plurality of switching devices 20 located in the same memory cell row are connected to the peripheral global source line GSL through a corresponding one of the source lines SL.

For example, the global source line GSL is grounded, thereby grounding the second terminal 23 of the switching device 20 of the switching devices in the plurality of memory cells 30.

For example, as shown in fig. 7A and 7B, the resistive random access memory array 70 further includes a plurality of initialization circuits 54 electrically connected to the plurality of bit lines in a one-to-one correspondence. Each initialization circuit comprises a control terminal, a first terminal and a second terminal, the control terminal of the initialization circuit is configured to receive an initialization control voltage, the first terminal of the initialization circuit is configured to receive an initialization operation voltage, the second terminal of the initialization circuit is electrically connected with a bit line correspondingly connected with the initialization circuit, and the initialization circuit is configured to respond to the initialization control voltage and write the initialization operation voltage into the corresponding bit line.

The resistive memory array 70 provided in this embodiment is mainly different from the resistive memory array 50 in the embodiment described with reference to fig. 3 in the way of disposing source lines, and for other structures, reference may be made to the description of the resistive memory array 50 in the foregoing embodiment. And will not be described in detail herein.

The embodiment of the present disclosure also provides an operation method, which is used for operating the resistive random access memory array 70. The operation method comprises the following steps: the method comprises the steps of applying word line voltage to a plurality of word lines to select a row of memory cells, applying source line voltage to a second end of a switch device of the selected row of memory cells to enable the switch device to be started and transmitting the source line voltage to a first electrode of a resistive switching device of the selected row of memory cells, and applying read-write operation voltage or initialization operation voltage to a second electrode of the resistive switching device of at least one of the selected row of memory cells through at least one of a plurality of bit lines. The read and write operation voltage includes at least one of a program operation voltage, an erase operation voltage, and a read operation voltage.

Since the second terminals 23 of the switching devices 20 of each row of memory cells are connected to each other at the same potential, when performing various operations, such as an initialization operation, a program operation, an erase operation, and a read operation, with the potential of the first electrode 11 directly connected to the resistive switching device and the switching device 20 as a reference potential, the initialization operation voltage, the program operation voltage, the erase operation voltage, and the read operation voltage may be applied to the second electrode 12 of the resistive switching device 10 of the selected memory cell through the bit line.

For example, the source line voltage is a ground voltage. Thus, the initialization operation, the program operation, and the read operation may be performed by applying a positive voltage through the bit line, and the erase operation may be performed by applying a negative voltage. This helps to reduce the voltage amplitude requirement and thus the voltage withstand requirements of the circuit.

The operation method provided by the embodiment of the present disclosure is exemplarily described below with reference to fig. 7B. The operation method includes, for example, an initialization operation phase, a program operation phase, an erase operation phase, and a read operation phase. For example, the first transistor T1 and the second transistor T2 are both N-type transistors; the third transistor T3 is a P-type transistor. However, the disclosed embodiments do not limit the types of the first to third transistors, and when the types of the transistors are changed, the magnitude relationship between the signals is adjusted accordingly so that the circuits realize the same function.

For example, during an initialization operation, a word line voltage V is applied through a selected word line WL (corresponding to one or more rows of selected memory cells connected thereto)_WLTurns on and controls the global source line GSL to be grounded, thereby turning on the switching device 20 (the first transistor T1) of the selected row or rows of memory cells 30.

For example, a block selection voltage V is applied to the block selection circuit 53 through the block selection line BSL_BSThe block selection circuit 53 is turned off. For example, the control block select line BSL is grounded such that the second transistor T2 is turned off. Thus, during the initialization operation in the initialization operation stage, the block selection circuit is turned off to separate the transmission of the initialization circuit and the initialization operation voltage from the transmission of other control circuits and operation voltages, thereby reducing the circuit range involved by the initialization operation voltage and reducing the withstand voltage requirement and size of the circuit.

For example, the initialization operation voltage V is applied to the initialization operation lines FL_FAn initialization control voltage V is applied to the initialization control line FCL_FCThe third transistor T3 is turned on to turn on the initialization circuit.

For example, the third transistor T3 is a P-type transistor, and the initialization voltage V is applied to the initialization operation line FL during the initialization operation phase_FApplying initialization control to the initialization control line FCLSystem voltage V_FCAnd makes the initialization operation voltage V_FIs higher than the initialization control voltage V_FCThereby turning on the third transistor T3, the initialization circuit 54 is turned on. For example, the initialization operating voltage V_FBetween 2V and 6V. For example, the initialization control voltage V_FCPulse time (T) of_F) In the range of 1 microsecond to 10 milliseconds.

For example, the initialization operation voltage V is applied through the initialization circuit 54 and the plurality of bit lines BL_FA second electrode 12 applied to the resistive switching device 10 of the selected at least one row of memory cells; the first electrode 11 of the resistive device is grounded through the turned-on switching device 20, so that a voltage difference V is introduced between the two ends of the resistive device_FThe resistive switching device is broken down to change from an initial high resistance state to a low resistance state, so that at least one row of memory cells selected are simultaneously subjected to an initialization (Forming) operation.

For example, during a program operation phase, the plurality of initialization circuits are turned off, and the block selection circuit is turned on; applying a positive program operation voltage V to a selected memory cell through at least one block selection circuit 53 and at least one bit line BL_SetAnd controlling the global source line GSL to be grounded, so that a forward voltage is applied to the resistance change device to program the memory cell.

For example, a positive block select voltage V_BSApplied to the block selection line of the selected resistive random access memory array, and programmed with the operating voltage V_SetIs applied to at least one global bit line GBL to turn on the corresponding at least one block selection circuit, and transfers the program operation voltage to the corresponding bit line BL and to the second electrode 12 of the resistive switching device of the selected memory cell.

For example, a positive word line voltage V_WLThe switching device in the selected memory cell in a row of memory cells 30 is turned on by applying the selected word line WL (corresponding to the connection of the selected memory cell) to the control terminal of the switching device 20 (first transistor T1) in the row of memory cells, and the first electrode 11 of the resistive switching device is grounded.

For example, the program operation voltage V_SetIs as large as1.2V-3V, and the pulse time is between 1 nanosecond and 10 microseconds.

For example, during an erase operation, the plurality of initialization circuits are turned off and the block selection circuit is turned on; applying a negative erase operation voltage V to the selected memory cell through at least one block selection circuit 53 and at least one bit line BL_RSTAnd controlling the global source line GSL to be grounded, so that reverse voltage is applied to the resistance change device to erase the memory unit.

For example, a positive block select voltage V_BSApplied to the block selection line of the selected resistive random access memory array, and applying an erase operation voltage V_RSTIs applied to at least one global bit line GBL to turn on the corresponding at least one block selection circuit, and applies the negative erase operation voltage V_RSTTransferred to the corresponding bit line BL and applied to the second electrode 12 of the resistance change device of the selected memory cell.

For example, a positive word line voltage V_WLThe switching device in the selected memory cell in a row of memory cells 30 is turned on by applying a selected word line WL (corresponding to the connection of the selected memory cell) to the control terminal of the switching device 20 in the row of memory cells, and the first electrode 11 of the resistive switching device is grounded.

For example, the erase operation voltage V_RSTIs between-1.2V and-3V, and the pulse time is between 1 nanosecond and 10 microseconds.

For example, with combined reference to FIG. 7B, a positive block select voltage V is applied_BSIs applied to a block selection line of a selected resistive random access memory array, and a read operation voltage V_ReadIs applied to at least one global bit line GBL (corresponding to the selected memory cell connected) to turn on the at least one block selection circuit and to turn on the read operation voltage V_ReadTo the second electrode 12 of the resistance change device of the selected memory cell through the corresponding bit line BL.

For example, a positive word line voltage V_WLThe switching device in the selected memory cell in a row of memory cells 30 is turned on by applying the selected word line WL (corresponding to the connection of the selected memory cell) to the control terminal of the switching device 20 (first transistor T1) and grounding the global source line GSL, and the first electrode 11 of the resistive switching device is grounded.

Positive V is introduced to two ends of electrodes of resistance change device of selected memory cell_ReadA voltage difference and generates an on read current (IRead). The resistance value of the resistance change device is high, and the reading current is small; the resistance value is low and the reading current is large. The read current is detected by the peripheral read control circuit to complete the read operation of the selected memory cell.

For example, the read operation voltage V_ReadBetween 0.1V and 1.2V, the pulse time is in the range of 1 nanosecond to 10 microseconds.

For example, the method of operation may include a multi-step initialization operation. For example, the operation method provided in the embodiment shown in fig. 5 is also applicable to the resistive random access memory array 70, and is not described herein again.

The embodiment of the present disclosure further provides a resistive random access memory circuit 80, which includes the resistive random access memory circuit 70.

Fig. 8 is a schematic structural diagram of a resistive random access memory circuit 80 according to at least one embodiment of the present disclosure. As shown in fig. 8, the resistance change memory circuit 80 further includes a source line control circuit 81 configured to be electrically connected to the second terminals of the switching devices of the memory cells of the one or more memory cell rows to supply a source line voltage.

For example, the source line control circuit 81 may be connected to a plurality of source lines SL to supply source line voltages to a plurality of memory cell rows, respectively. The source line voltages received by the row of memory cells may be the same or different.

For example, the source line control circuit 81 may also be electrically connected to the global source line GSL to supply a source line voltage to the resistive memory array 70.

For example, the global source line GSL may be directly grounded, and in this case, the source line control circuit 81 may be omitted.

For example, the resistance change memory circuit 80 further includes an initialization control circuit 82, the initialization control circuit 82 being configured to be electrically connected with the plurality of initialization circuits 54 to provide the initialization operation voltage_VFAnd the initialization control voltage V_FC。

For example, as shown in fig. 8, the resistance change memory circuit 80 further includes a column selection circuit 83, and the column selection circuit 83 is configured to be connected to the plurality of block selection circuits 53 to supply read and write operation voltages to the resistance change memory array 70. For example, the read/write operation voltage includes a program operation voltage V_SetErase operation voltage V_RSTAnd a read operation voltage V_Read。

For example, the column selection circuit 83 is electrically connected to a plurality of global bit lines GBL.

For example, the resistance change memory circuit 80 further includes a program and erase control circuit 84 and a read control circuit 85.

For example, the program and erase control circuit 84 is connected to the column selection circuit 83, and is configured to provide the program operation voltage V to the resistive random access memory array 70 through the column selection circuit 83_SetAnd the erasing operation voltage V_RST。

For example, in a program operation phase, the program and erase control circuit 84 applies a positive program operation voltage V to a selected memory cell through the column selection circuit 83 and at least one bit line BL_SetAnd applying a forward voltage to the resistive switching device to perform a programming operation on the memory cell.

For example, in the erase operation phase, the program and erase control circuit 84 applies a negative erase operation voltage V to the selected memory cell through the column selection circuit 83 and at least one bit line BL_RSTAnd applying a reverse voltage to the resistive switching device to perform an erase operation on the memory cell.

Since the program operation voltage and the erase operation voltage are applied to the memory cells through the bit lines, the program control circuit and the erase control circuit can be integrated into the same circuit module. For example, the program and erase control circuit 84 includes a positive voltage generation circuit and a negative voltage generation circuit to generate a positive program operation voltage during the program operation phase and a negative erase operation voltage during the erase operation phase, respectively.

For example, the read control circuit 85 is connected to the column selection circuit 83 and configured to provide the read operation voltage V to the resistive random access memory array 70 through the column selection circuit 83_Read. For example, in a read operation phase, the read control circuit 85 applies a read operation voltage V to a selected memory cell through the column selection circuit 83 and at least one bit line BL_ReadAnd applying a forward voltage to the resistive switching device to perform a read operation on the memory cell.

For example, as shown in fig. 8, the resistance change memory circuit 80 further includes a block selection control circuit 86 and a word line control circuit 87.

For example, the block selection control circuit 86 is configured to be connected with the block selection line BSL to supply the block selection voltage V to the resistive memory array 70_BS。

For example, the word line control circuit 87 is configured to provide the word line voltage V to the resistive random access memory array 70_WL. For example, the word line control circuit 87 is electrically connected to a plurality of word lines WL.

At least one embodiment of the present disclosure also provides an electronic apparatus including the resistance change memory circuit of any one of the above embodiments, which may be a memory device, a hard disk, a mobile device, a mobile phone, a notebook computer, a desktop computer, or the like.

The above description is intended to be exemplary of the present disclosure, and not to limit the scope of the present disclosure, which is defined by the claims appended hereto.

Claims

1. An operation method of a resistance change memory array, the resistance change memory array comprising:

the memory cell array comprises a plurality of memory cells, a plurality of memory cell rows and a plurality of memory cell columns, wherein each memory cell comprises a resistance change device and a switch device, the resistance change device comprises a first electrode and a second electrode, and the first electrode of the resistance change device is electrically connected with the switch device;

a plurality of bit lines extending in the second direction and respectively connected to the plurality of memory cell columns, wherein each of the plurality of bit lines is electrically connected to the second electrode of the resistive switching device of the memory cell of the corresponding one of the memory cell columns;

a plurality of word lines extending in the first direction and respectively connected to the plurality of memory cell rows, wherein each of the plurality of word lines is electrically connected to the switching device of the memory cell of a corresponding one of the memory cell rows;

a plurality of block selection circuits electrically connected to the plurality of bit lines in a one-to-one correspondence; and

the plurality of initialization circuits are respectively electrically connected with the plurality of bit lines in a one-to-one correspondence manner;

the operation method comprises the following steps:

turning off the plurality of block selection circuits, and performing first initialization operation and second initialization operation on the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines, wherein the first initialization operation is prior to the second initialization operation;

wherein the first initialization operation comprises: applying a first initialization operation voltage V to memory cells of a selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines_F1；

The second initialization operation includes: applying a second initialization operation voltage V to the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines_F2。

2. The operating method of claim 1, wherein the first initialization operating voltage V_F1 is greater than the second initialization operating voltage V_F2。

3. The operating method of claim 1, wherein each initialization circuit includes a control terminal, a first terminal, and a second terminal, the second terminal of each initialization circuit being electrically connected to a bit line to which the initialization circuit is correspondingly connected;

the first initialization operation further includes: applying a first initialization control voltage V to control terminals of the plurality of initialization circuits_FC1 to turn on the plurality of initialization circuits,

the second initialization operation further includes: applying a second initialization control voltage V to the plurality of initialization circuits_FC2 to turn on the plurality of initialization circuits.

4. The operating method of claim 3, wherein each of the plurality of initialization circuits comprises a switching transistor having a gate, a first pole, and a second pole, respectively, that are a control terminal, a first terminal, and a second terminal of the initialization circuit; the switching transistor is a P-type transistor,

the first initialization control voltage V_FC1 is less than the first initialization operating voltage V_F1, the second initialization control voltage V_FC2 is less than the second initialization operation voltage V_F2。

5. The operating method of claim 3, wherein a difference | V between the first initialization operating voltage and the first initialization control voltage_F1－V_FC1 is less than the difference | V between the second initialization operation voltage and the second initialization control voltage_F2－V_FC2|。

6. The operating method of claim 1, wherein a time of the first initialization operation is greater than a time of the second initialization operation.

7. The method of operation of any of claims 1-6, further comprising:

performing a third initialization operation on the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines after the second initialization operation,

wherein the third initialization operation comprises: applying a third initialization operation voltage V to the memory cells of the selected at least one memory cell row through the plurality of initialization circuits and the plurality of bit lines_F3。

8. The operating method of claim 7, wherein the first initialization operating voltage V_F1. The second initialization operation voltage V_F2. The third initialization operation voltage V_FThe size of 3 decreases in turn.

9. The operating method of claim 7, wherein operation times of the first initialization operation, the second initialization operation, and the third initialization operation are sequentially decreased.

10. The operating method of claim 7, wherein each initialization circuit includes a control terminal, a first terminal, and a second terminal, the second terminal of each initialization circuit being electrically connected to a bit line to which the initialization circuit is correspondingly connected;

the first initialization operation further includes: applying a first initialization control voltage V to control terminals of the plurality of initialization circuits_FC1 to turn on the plurality of initialization circuits;

the second initialization operation further includes: applying a second initialization control voltage V to the plurality of initialization circuits_FC2 to turn on the plurality of initialization circuits;

the third initialization operation further includes: applying a third initialization control voltage V to the plurality of initialization circuits_FC3 to turn on the plurality of initialization circuits,

a difference | V between the first initialization operation voltage and the first initialization control voltage_F1－V_FC1, a difference | V between the second initialization operation voltage and the second initialization control voltage_F2－V_FC2, a difference | V between the third initialization operation voltage and the third initialization control voltage_F3－V_FC3| are sequentially increased.